Each of the following questions (1-15) is worth 6 points

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1 Name: S. I. D.: Physics 0 Final Exam (Version A) Summer 06 HIS EXAM CONAINS 36 QUESIONS. ANSWERS ARE ROUNDED. PICK HE BES ANSWER O EACH QUESION. Each of the following questions ( - 5) is worth 6 points. A ertical block-spring system on earth has a period of 6.0 s. What is the period of this same system on the moon where the acceleration due to graity is roughly /6 that of earth? A).0 s B).4 s C) 6.0 s D) 5 s E) 36 s. Which one of the following statements is true concerning an object executing simple harmonic motion? A) Its elocity is neer zero. B) Its acceleration is neer zero. C) Its elocity and acceleration are simultaneously zero. D) Its elocity is zero when its acceleration is a maximum. E) Its maximum acceleration is equal to its maximum elocity. 3. he elocity of a certain simple harmonic oscillator is gien by ( m/s) sin [(6.0 rad/s) t]. What is the amplitude of the simple harmonic motion? A).0 m B) 4.0 m C) 6.0 m D) 8.0 m E) m Page

2 4. Complete the following statement: Young's modulus cannot be applied to A) a stretched wire. B) a compressed rod. C) a bending beam. D) a compressed liquid. E) a stretched rubber band. 5. In a car lift, compressed air with a gauge pressure of Pa is used to raise a piston with a circular cross-sectional area. If the radius of the piston is 0.7 m, what is the maximum mass that can be raised using this piston? A) 530 kg B) 3700 kg C) 9800 kg D) 000 kg E) kg 6. Which one of the following statements concerning the buoyant force on an object submerged in a liquid is true? A) he buoyant force depends on the mass of the object. B) he buoyant force depends on the weight of the object. C) he buoyant force is independent of the density of the liquid. D) he buoyant force depends on the olume of the liquid displaced. E) he buoyant force will increase with depth if the liquid is incompressible. 7. hree thermometers are in the same water bath. After thermal equilibrium is established, it is found that the Celsius thermometer reads 00 C, the Fahrenheit thermometer reads F, and the Kelin thermometer reads 73 K. Which one of the following statements is the most reasonable conclusion? A) he Kelin thermometer is incorrect. B) he Celsius thermometer is incorrect. C) he Fahrenheit thermometer is incorrect. D) All three thermometers are incorrect. E) he three thermometers are at different temperatures. Page

3 8. Which one of the following statements best explains why conection does not occur in solids? A) Molecules in a solid are more closely spaced than in a gas. B) he molecules in a solid are not free to moe throughout its olume. C) Molecules in a solid ibrate at a lower frequency than those of a liquid. D) Solids are more compressible than liquids. E) Solids are less compressible than gases. 9. A granite wall has a thickness of 0.6 m and a thermal conductiity of. W/(m C ). he temperature on one face of the wall is 3. C and 0.0 C on the opposite face. How much heat is transferred in one hour through each square meter of the granite wall? A) J/m B) J/m C) J/m D) 800 J/m E) 58 J/m 0. he power radiated by a distant star is W. he radius of the star, which may be considered a perfect radiator, is m. Determine the surface temperature of the star. A) 690 K B) 4430 K C) 740 K D) 850 K E) 9770 K. Argon gas at 305 K is confined within a constant olume at a pressure P. If the gas has a pressure P when it is cooled to 95 K, what is the ratio of P to P? A) 0.40 B) C) 0.77 D).8 E).56 Page 3

4 . Complete the following statement: Walls that separate a system from its surroundings and permit heat to flow through them are called A) diathermal walls. B) adiabatic walls. C) entropic walls. D) isobaric walls. E) isochoric walls. 3. An ideal gas absorbs 750 J of heat as it performs 65 J of work. What is the resulting change in temperature if there is.3 moles of the gas? A) 8.6 K B) 4.3 K C) 7.7 K D) 9.6 K E) 3 K 4. Calculate the speed of the oxygen molecules in the air if the temperature is 5.00 C. Note: he mass of the oxygen molecule is u. A) 6.0 m/s B) 86.3 m/s C) 38 m/s D) 465 m/s E) 487 m/s 5. In a reersible heat engine, one mole of an ideal gas is carried through a circular cycle beginning and ending at point A as shown in the figure. Which one of the following statements concerning this system is false? A) he entropy must increase in one cycle. B) he heat added in one cycle must be 34 J. C) he work done in completing one cycle is 34 J. D) he change in internal energy for one cycle is zero. E) he internal energy for this system is dependent on its state. Page 4

5 Each of the following questions (6-36) is worth 0 points 6. A.0-kg object is suspended from a spring with k 6 N/m. he mass is pulled 0.5 m downward from its equilibrium position and allowed to oscillate. What is the maximum kinetic energy of the object? A) 0.5 J B) 0.50 J C).0 J D).0 J E) 4.0 J 7. An iron ball hangs from a 4-m steel cable and is used in the demolition of a building at a location where the acceleration due to graity is 9.9 m/s. he ball is swung outward from its equilibrium position for a distance of 4.5 m. Assuming the system behaes as a simple pendulum, find the maximum speed of the ball during its swing. A).9 m/s B) 7.0 m/s C) m/s D).9 m/s E) 9.8 m/s 8. he aerage density of the material in intergalactic space is approximately kg/m 3. What is the olume of a gold sample, ρ kg/m 3, that has the same mass as m 3 of intergalactic space? A) m 3 B) m 3 C) m 3 D) m 3 E) m 3 Page 5

6 9. A gas sample is confined to a chamber with a moable piston. A small load is placed on the piston and the system is allowed to reach equilibrium. If the weight of the piston and the load is 70.0 N and the piston has an area of m, what is the pressure exerted on the piston by the gas? Note: Atmospheric pressure is Pa. A) Pa B) Pa C) Pa D) Pa E) Pa 0. At a location where the acceleration due to graity is m/s, the atmospheric pressure is Pa. A barometer at the same location is filled with an unknown liquid. What is the density of the unknown liquid if its height in the barometer is.63 m? A) 0 kg/m 3 B) 4336 kg/m 3 C) 537 kg/m 3 D) 867 kg/m 3 E) 9688 kg/m 3. A child wants to pump up a bicycle tire so that its pressure is Pa aboe that of atmospheric pressure. If the child uses a pump with a circular piston m in diameter, what force must the child exert? A) 0 N B) 40 N C) 340 N D) 930 N E) 300 N Page 6

7 . A -kg block displaces 0 kg of water when it is held fully immersed. he object is then tied down as shown in the figure; and it displaces 5 kg of water. What is the tension in the string? A) 0 N B) 0 N C) 30 N D) 70 N E) 00 N 3. Which one of the following statements concerning streamline flow is true? A) At any gien point in the fluid, the elocity is constant in time. B) Streamline flow occurs when there are sharp obstacles in the path of a fast-moing fluid. C) Streamline flow is described by Pascal's principle. D) Streamline flow is described by Archimedes' principle. E) he elocity ectors are the same for all particles in the fluid. 4. Water is flowing through a channel that is m wide with a speed of 0.75 m/s. he water then flows into four identical channels which hae a width of 4.0 m. he depth of the water does not change as it flows into the four channels. What is the speed of the water in one of the smaller channels? A) 0.56 m/s B).3 m/s C) 0.5 m/s D) 0.75 m/s E) 0. m/s Page 7

8 5. he coefficient of linear expansion of aluminum is /C. A circular hole in an aluminum plate is.75 cm in diameter at 0 C. What is the diameter of the hole if the temperature of the plate is raised to 00 C? A) cm B).78 cm C).73 cm D).757 cm E).788 cm 6. At a certain temperature, a simple pendulum has a period of.500 seconds. he support wire is made of siler and has a coefficient of linear thermal expansion of /C. How much must the temperature be increased to increase the period to.506 seconds? A) 8 C B) C C) 36 C D) 434 C E) 58 C 7. wo spheres, labeled A and B hae identical masses, but are made different substances. he specific heat capacity of sphere A is 440 J/kg C and that of sphere B is 60 J/kg C. he spheres are initially at C; and the same quanity of heat is added to each sphere. If the final temperature of sphere A is 7 C, what ifs the final temperature of sphere B? A) 60 C B) 40 C C) C D) 5 C E) 39 C 8. Determine the latent heat of aporization of unknown substance X in kcal/g if 3.0 g of boiling liquid X are completely aporized in.5 hours by an energy source of 0 kcal/h. A) 5 kcal/g B) 5 kcal/g C) 7 kcal/g D) 30 kcal/g E) 57.9 kcal/g Page 8

9 9. A slab of insulation is made of three layers, as Drawing I indicates. Each of the layers A, B, and C has the same thickness, but a different thermal conductiity. Heat flows through the slab, and the temperatures are as shown. What are the temperatures and In Drawing II where the layers are arranged in a different order? A) 30 C and 70 C B) 00 C and 80 C C) 0 C and 60 C D) 80 C and 60 C E) 0 C and 90 C 30. An ideal gas with a fixed number of molecules is maintained at a constant pressure. At 30.0 C, the olume of the gas is.50 m 3. What is the olume of the gas when the temperature is increased to 75.0 C? A) 0.60 m 3 B).30 m 3 C).7 m 3 D).45 m 3 E) 3.75 m 3 Page 9

10 3. Enclosed beneath the moeable piston in the figure is 4.8 moles of a monatomic ideal gas. he gas performs work on the piston as 300 J of heat are added from the surroundings. During the process, the temperature of the gas decreases by 45 K. How much work does the gas perform? A) 5000 J B) 300 J C) 400 J D) 600 J E) 400 J 3. What change in temperature occurs when 00 J of heat are remoed from 4.0 moles of monatomic gas under constant pressure? A) 8.3 K B) K C) 4 K D) 8 K E) 36 K 33. A gasoline engine with an efficiency of 0.40 generates 500 W of power. If a liter of gasoline has an energy content of J, how many liters of gasoline does the engine consume each hour? A) 0.36 B) 0.48 C).4 D).8 E) 6.9 Page 0

11 34. A wae has an amplitude of 0.35 m, a frequency of Hz, and traels in the positie x direction at the speed of light, m/s. Which one of the following equations correctly represents this wae? A) y 0.35 sin ( t 0.0x) B) y 0.35 sin ( t + 0.0x) C) y 0.35 sin (86t x) D) y 0.35 sin (86t x) E) y 0.35 sin ( t x) 35. A source moing through water at 0 m/s generates water waes with a frequency of 5.0 Hz. he speed of these water waes relatie to the water surface is 0.0 m/s. he source approaches an obserer who is at rest in the water. What waelength would be measured for these waes by the stationary obserer? A).0 m B).0 m C) 4.0 m D) 6.0 m E) 8.0 m 36. A certain string on a piano is tuned to produce middle C (f 6.63 Hz) by carefully adjusting the tension in the string. For a fixed waelength, what is the frequency when this tension is doubled? A) Hz B) Hz C) Hz D) Hz E) 53.6 Hz Page

12 Page Some Equations You Might Find Useful: ω π π ω f L g m k pen spr ω ω kx F kx t A d ) sin(ω F B W fluid A F P V m ρ KE k gh P gh P A A β ρ ρ ρ ρ ρ μ Y F L L Y A F 0 ρ γ π B m k r P I 4 K mol J R m W I I I f * ) 0log( 0 0 β λ ± ± sound source sound obs source obs f f Nk U nr PV B C F V V L L β α 0 0 V P W ml Q cm Q i f V V nr W W Q U ln k KE k m trans β β 3 3

13 Page 3 Pa atm N K J k kx PE A β H C pump H C H C R H C H C e e e Q Q e

14 Answer Key -- final "summer06". C. D 3. A 4. D 5. B 6. D 7. A 8. B 9. A 0. A. B. A 3. C 4. D 5. A 6. B 7. D 8. A 9. E 0. A. D. B 3. C 4. A 5. C 6. C 7. A 8. A 9. C 30. C 3. A 3. C 33. A 34. A 35. B 36. C Page 4